Wire crimping tool



July 29, 1969 w. H. MCKEE 3,457,764

WIRE CRIMPING TOOL Filed D60. 4, 1967 United States Patent Office 3,457,764 Patented July 29, 1969 3,457,764 WIRE CRIMPING TOOL William H. McKee, West Covina, 'Calif., assignor, by

mesne assignments, to United-Carr Incorporated, Boston, Mass., a corporation of Delaware Filed Dec. 4, 1967, Ser. No. 687,655 Int. Cl. B21d 9/08; H01r 11/04 US. Cl. 72-410 Claims ABSTRACT OF THE DISCLOSURE This invention is directed at a wire crimping tool having a wire receiving recess which acts as a stop which has a rotatable element to provide a gauge for proper engagement of the insulation and the stripped wire by the contact to be crimped.

BACKGROUND OF THE INVENTION Most open type crimp tools require that the wire lead be visually positioned in the crimp pocket. This requires that one hand holds the wire lead in position while the other hand operates the tool. There is a tendency to pull the wire out of the pocket as the tool is operated. This action prevents a proper crimp of the contact with the insulated part of the lead wire. If an improper crimp is made on the insulation the wire is more likely, without the insulation support, to bend and break at the plane where the insulation ends.

On the other hand, if the operator should overcompensate and push the wire lead in too far, the insulation could get into the conductor crimp portion preventing a good electrical connection and the wire end may extend beyond the contact crimp area and interfere with the function of the remaining portion of the contact such as engagement to an insulator or mating with other terminals.

Early crimping tools did not use any stops at all and pioneer tools did not provide any means of holding the contact unless slight pressure was applied by the crimping aws. 1 An improvement on the early tools was the use of a thin blade which was sandwiched between one of the jaws and which extended toward the other jaw. This blade positioned the contact and had a hole through it which could be used as a stop since it was of such small diameter that the stripped wire would pass through and prevent the insulation from passing through. This tool is difficult to use because the extremely small hole is hard to locate.

SUMMARY OF THE INVENTION- An object of the present invention is to provide a crimping tool having a gauge for positioning the wire lead.

A further object of the present invention is to provide a stop means for a wire crimping tool that moves out of the way to provide contact loading and unloading.

The present invention is a manually operated crimping tool of parallel, one-plane construction having a fixed jaw and a movable jaw. The movable jaw having a movable stop member associated therewith.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of the crimping tool with the handles broken off;

FIG. 2 is a bottom plan view of the head of the crimping tool shown in FIG. 1;

FIG. 3 is a perspective view of the stop means shown in FIG. 2;

FIG. 4 is a section taken on line 44 of FIG. 1 showing the stop means disengaged; and

FIG. 5 is the section shown in FIG. 4 with the stop means engaged.

DESCRIPTION OF THE PREFERRED EMBODIMENT There is shown in the drawings a hand tool having a head 10 which has a rectangular aperture 12 formed therethrough. A fixed die 14 is mounted in the upper portion of the aperture 12 with its upper jaw directed away fromthe upper surface of the head 10. The upper jaw has a pair of deep arcs formed therein formed with the right-hand arc 16 slightly deeper than the left-hand are 18. Both arcs 16 and 18 are provided with an internal shoulder 20, which follows the inner surface of the jaw for a purpose to be described hereinafter.

A movable die 22 is mounted in the lower portion of the rectangular aperture 12 and comprises a lower jaw 24 which is generally rectangular in shape, which has a pair of spaced fingers 26 extending from an edge thereof and which is attached to a die base 28 through a rectangular spacer element 30. The free ends 32 of the fingers 26 have shallow arced depressions formed therein for a purpose to be described hereinafter. J

The die base 28 has a platform portion 34 extending from one side thereof and in right angle thereto. The lower surface of the platform portion 34 has a slot 38 formed therein which is partially capped by a cover, thereby providing a recess for engagement with a flanged member, as will be more fully set forth hereinafter. The end surface of the die base 28 opposite that from which the platform portion 34 extends has a pair of spaced terminal receiving recesses 40 formed therein and which in turn are covered on the end surface by a stop plate 42.

A movable stop member 44 comprises a base portion 46 bent at right angles at each of its ends to provide sidewalls 48. A pair of arms 50 extending from the mid-portion of an edge of the base portion 46 are each bent at right angles to the plane of the base portion 46 as shown in FIG. 3. The terminal end of each of the sidewalls 48 has a flexible, rectangular tang 52 extending therefrom which is spaced for the major portion of its length from the remaining part of the sidewall 48 and which has adjacent its free terminal end an inwardly extending protuberance 54. The stop member 44 is movably attached to the die base '28 so that it may be manually rotated to place the two arms 50 in a spatially covered relationship to the contact receiving recesses 40 with the protuberances 54 of the tangs 52 butted against an edge of the die base 28. A ratchet tooth 37 extends from each of the side walls 48 in a direction opposite to that of the rectangular tang 52 for the purpose to be described hereinafter. The movable die 22 is slideably confined within the rectangular aperture 12 by attaching a yoke portion 56 to the die base 28 so that the ears of the movable die 22 travels on the same plane as the fixed die 14 and toward it by pressing a movable handle 58 toward a fixed handle in a manner similar to that described in the United States Patent to W. R. Over, US. 3,075,198.

To attach a wire termination 60 to an insulated wire 62 using the disclosed hand tool, the termination 60 is dropped into one of the contact receiving recesses 40, engagement portion first, with its arced back butted against a shallow are or depression 32 formed at the end of the finger 26 which is directed at the appropriate are 16 or 18. Two pairs of ears in spaced relation to each other extend from the arced back of the termination 60 and are directed toward the are 16, for example, when the termination 60 is engaged in the tool. At this time the stop member 44 is in a position whereby the arms 50 do not overlie the contact receiving recesses 40. After the termination 60 is engaged in the appropriate contact receiving recess 40, the stop member 44 is rotated, manually, placing the arms 50 on a predetermined plane below the pairs of ears of the terminal 60 as shown in FIG. 5. With its terminal end stripped, the insulated wire 62 is placed against the inner surface of the arced back and within the area defined by the two pairs of ears until it butts against the upper surface of one of the arms 50. At this time, the movable handle 58 is driven toward the fixed handle and the movable die 22 is moved toward the fixed die 14 making the crimp in a manner well known in the art. A pawl member 64 is attached to the head 10 and is formed of a flat piece of flexible steel or other appropriate flexible material such as a thermoplastic, for example. The pawl member 64 has a flexible pawl arm 66, which is extended toward the die base 28, and which has a gear tooth 68 extended therefrom adjacent the rectangular aperture 12. As the movable die 22 approaches the fixed die 14, the ratchet tooth 37 of the stop member 44 engages behind the gear tooth 68 so that, after the crimp is made, and as the movable die 22 leaves its engagement with the fixed die 14, the resistance of the gear tooth 68 to the planar movement of the ratchet tooth 37 causes the stop member 44 to rotate which, in turn, removes the arms 50 for their superposed position over the contact receiving recesses 40 allowing the crimped assembly to be withdrawn as well as preparing for the next crimping operation.

With reference to the foregoing description, it is to be understood that what has been disclosed herein represents several embodiments of the invention and is to be construed as illustrative rather than restrictive in nature and that the invention is best described by the following claims:

I claim:

1. A stop member for a contact crimping tool comprising a base portion having a pair of side walls extending therefrom, the side walls being in spaced parallel relation to each other, and having an arm extending from the base portion, said arm having its terminal end bent at an angle and said walls having means of engaging the contact crimping tool.

2. A stop member as set forth in claim 1 wherein the side walls are in right angle relation to the plane of the 4 base portion and the arm extends from an edge of the base portion and wherein a ratchet tooth extends from at least one of said side walls.

3. A stop member as set forth in claim 2 wherein each of the side walls has a tang extending therefrom in a direction opposite to that of the ratchet tooth and said tang has means of engaging the contact crimping tool.

4. A contact crimping tool comprising a fixed die, having a pocket formed therein, a movable die having at least one terminal receiving recess and a stop member comprising a base portion having a pair of side walls extending therefrom, the side walls being in spaced parallel relation to each other and having at least one arm extending from a base portion, said arm having its terminal end bent at an angle and said stop member rotatably attached to the movable die at the side walls whereby rotation of the stop member will place the terminal end of the arm over the terminal receiving recess preventing a lead wire from passing into the terminal receiving recess and means of moving the movable die toward the fixed die.

5. A contact crimping tool as set forth in claim 4 wherein at least one of said side walls of said stop member has a ratchet tooth extending forwardly therefrom and said fixed die and said movable die are set within a cavity formed in a head portion and said head portion has a pawl member from which a gear tooth extends, said gear tooth positioned to engage said ratchet tooth after the movable die has engaged the fixed die causing said stop member to rotate.

References Cited UNITED STATES PATENTS 9/1960 Lazar 29203 3,281,926 11/1966 Frastaci et al. 29-203 RONALD D. GREFE, Primary Examiner U.S. Cl. X.R. 29-203 

